1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause OR GPL-2.0 3 * 4 * This file is provided under a dual BSD/GPLv2 license. When using or 5 * redistributing this file, you may do so under either license. 6 * 7 * GPL LICENSE SUMMARY 8 * 9 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved. 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of version 2 of the GNU General Public License as 13 * published by the Free Software Foundation. 14 * 15 * This program is distributed in the hope that it will be useful, but 16 * WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 18 * General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public License 21 * along with this program; if not, write to the Free Software 22 * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. 23 * The full GNU General Public License is included in this distribution 24 * in the file called LICENSE.GPL. 25 * 26 * BSD LICENSE 27 * 28 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved. 29 * All rights reserved. 30 * 31 * Redistribution and use in source and binary forms, with or without 32 * modification, are permitted provided that the following conditions 33 * are met: 34 * 35 * * Redistributions of source code must retain the above copyright 36 * notice, this list of conditions and the following disclaimer. 37 * * Redistributions in binary form must reproduce the above copyright 38 * notice, this list of conditions and the following disclaimer in 39 * the documentation and/or other materials provided with the 40 * distribution. 41 * 42 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 43 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 44 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 45 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 46 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 47 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 48 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 49 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 50 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 51 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 52 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 53 */ 54 55 #include <sys/cdefs.h> 56 /** 57 * @file 58 * 59 * @brief This file contains the base subject method implementations and 60 * any constants or structures private to the base subject object. 61 * A subject is a participant in the observer design pattern. A 62 * subject represents the object being observed. 63 */ 64 65 #include <dev/isci/scil/sci_types.h> 66 #include <dev/isci/scil/sci_base_subject.h> 67 #include <dev/isci/scil/sci_base_observer.h> 68 69 #if defined(SCI_LOGGING) 70 71 //****************************************************************************** 72 //* P R O T E C T E D M E T H O D S 73 //****************************************************************************** 74 75 void sci_base_subject_construct( 76 SCI_BASE_SUBJECT_T *this_subject 77 ) 78 { 79 this_subject->observer_list = NULL; 80 } 81 82 // --------------------------------------------------------------------------- 83 84 void sci_base_subject_notify( 85 SCI_BASE_SUBJECT_T *this_subject 86 ) 87 { 88 SCI_BASE_OBSERVER_T *this_observer = this_subject->observer_list; 89 90 while (this_observer != NULL) 91 { 92 sci_base_observer_update(this_observer, this_subject); 93 94 this_observer = this_observer->next; 95 } 96 } 97 98 // --------------------------------------------------------------------------- 99 100 void sci_base_subject_attach_observer( 101 SCI_BASE_SUBJECT_T *this_subject, 102 SCI_BASE_OBSERVER_T *observer 103 ) 104 { 105 observer->next = this_subject->observer_list; 106 107 this_subject->observer_list = observer; 108 } 109 110 // --------------------------------------------------------------------------- 111 112 void sci_base_subject_detach_observer( 113 SCI_BASE_SUBJECT_T *this_subject, 114 SCI_BASE_OBSERVER_T *observer 115 ) 116 { 117 SCI_BASE_OBSERVER_T *current_observer = this_subject->observer_list; 118 SCI_BASE_OBSERVER_T *previous_observer = NULL; 119 120 // Search list for the item to remove 121 while ( 122 current_observer != NULL 123 && current_observer != observer 124 ) 125 { 126 previous_observer = current_observer; 127 current_observer = current_observer->next; 128 } 129 130 // Was this observer in the list? 131 if (current_observer == observer) 132 { 133 if (previous_observer != NULL) 134 { 135 // Remove from middle or end of list 136 previous_observer->next = observer->next; 137 } 138 else 139 { 140 // Remove from the front of the list 141 this_subject->observer_list = observer->next; 142 } 143 144 // protect the list so people dont follow bad pointers 145 observer->next = NULL; 146 } 147 } 148 149 #endif // defined(SCI_LOGGING) 150